The Duchess of Cambridge was famously given a sapphire and diamond engagement ring when Prince William proposed.
The jewel had a central 12-carat oval sapphire which was surrounded by 14 diamonds.
She showed off the ring at a photo call which took place at St James Palace shortly after their engagement was announced.
The beautiful ring is estimated to be worth as much as £300,000 and once belonged to Prince William’s mother, Princess Diana.
READ MORE: Kate Middleton given £1k ring from William
At their wedding, Kate was given a wedding band made from Welsh gold, in line with royal tradition.
Since then, she has worked as a full-time member of the Royal Family which sometimes involves attending very important royal events.
On such occasions, the Duchess of Cambridge has sometimes borrowed pieces of royal jewellery.
However, she has recently been spotted wearing a piece that is not part of any royal collection.
The mother-of-three has attracted attention by wearing a ring that could be worth a huge amount of money, according to managing director at Miltons Diamonds Ben Johnson.
“The ring looks like a very large citrine stone to me and judging by the size of it could be worth anything from £5,000 up to £20,000,” he told Express.co.uk.
“Media reports have suggested that this ring is a new addition to the Duchess of Cambridge’s collection.
“But there is proof she owned it already, as she was photographed wearing it on a night out with Pippa in 2008.”
While the ring has turned heads recently, Kate first wore it many years before marrying Prince William.
By doing this, the expert claimed she could be sending a subtle message and showing her “independence” in the family.
Ben added: “The citrine rock could be making a reappearance because of what the stone is said to represent.
“It is widely claimed that the citrine crystal emanates optimism and can be used to direct personal will and decisiveness.
“This would explain the motivation behind Kate’s decision to wear it on occasions when she is not accompanied by the Duke of Cambridge, attending events on her own terms.
“She is an experienced royal now, capable and independent.”
Kate has been part of the Royal Family since 2011 and her choice of jewellery could confirm her growing confidence in her senior role.
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